The dos distribution contains all the files you need to run the compiler and compile Pascal programs.
Under unix systems (such as linux) you need to have the following programs installed :
The Windows distributions (both 32 and 64 bit) contain all the files you need to run the compiler and compile Pascal programs. However, it may be a good idea to install the mingw32 tools or the cygwin development tools. Links to both of these tools can be found on http://www.freePascal.org
While the Free Pascal distribution comes with all necessary tools, it is a good idea to install the
EMX extender in order to compile and run programs with the Free Pascal compiler. The EMX
extender can be found on:
Mac OS X 10.1 or higher is required, and the developer tools or XCode should be installed.